This prison was built between 1845 and 1850 by the architects Gilbert and Lecointe, on the general plans of the English prisons of the same nature, and was considered at the time a model institution. It succeeded the Prison de la Force, in the Rue Pavée-au-Marais, immortalized in a chapter of _Les Misérables_; the new prison was known officially as the Nouvelle-Force. Popular usage, however, gave it the name which it retained, from the Place Mazas, at the end of the Pont d'Austerlitz,--the name of the colonel of the Fourteenth Regiment of the line, killed at Austerlitz. His family protested strongly against this usage, and in 1858 the administration of prisons abandoned the popular term and recognized the institution only under the formula: _Maison d'arrêt cellulaire_. All in vain, even though, in 1879, the Boulevard Mazas became the Boulevard Diderot. This prison was the first in France in which was adopted solitary confinement. In a single night, that of the 19-20th of May, 1850, the eight hundred and forty-one inmates of the Force were transferred to Mazas,--a much more expeditious operation than that of the transportation of the prisoners of Mazas to the Santé, in May, 1898, which took ten days, at the rate of eighty men a day. It appears that the prisoners from the Force objected strongly to this system of solitary confinement in their cells; they gave way to such excesses of fury and despair that the Académie de Médecine was moved in their behalf, and protested against the _système cellulaire_ as conducive to suicide and insanity. The new prison--as any one might see from the top of the viaduct of the Vincennes railway--was built in the form of a great wheel, the spokes represented by six long galleries, eighty mètres in length and twelve and a half in height. The hub of this wheel was a two-story rotunda, the ground-floor of which was occupied by the central post of observation, and the upper story by the chapel, which could be seen from any point in any of the six galleries. At the hour of the celebration of the mass, on Sundays, the guards set the door of each cell partly open, so that the prisoner might receive spiritual comfort if he so pleased,--and if his distance were not too great. Each of the six galleries was two stories in height, lit by a glass roof. All the cells received light and air through a grated window, opening on one of the outside galleries or on one of the interior courts, but placed too high to afford the inmate any view outside. Each prisoner was entitled to an hour's exercise in one of the twenty préaux into which the interior courts were divided. This promenade was always a solitary one, under the eye of the guardians in the rotunda, and to be deprived of it was the lightest punishment inflicted. The most severe, in extreme cases, was imprisonment in the _cachot_, or dungeon.